Get Enough Sleep

We don't really know why we need to sleep, but scientists do have some theories. One is that reduced brain activity during non-REM ("rapid eye movement") sleep may give damaged brain cells and other cells of the body a chance to repair themselves during "off" time. Another theory is that sleep gives neurotransmitter receptors called monoamines, associated with mood and learning, a chance to recover from the day's activities. Still another theory holds that the brain needs to sleep in order to form new memories and generate new synaptic connections.

We may not know exactly why we sleep, but we do know what happens when you don't get enough sleep (7-8 hours a night for adults). If you miss an entire night of sleep but then get adequate sleep on the following 3 nights, you'll recover most of your normal ability to function. But if you get only 5 hours of sleep a night for weeks, you build up a cumulative sleep deficit. Your performance will be as impaired as if you'd been awake all night, and it will take 2-3 weeks of extra nightly sleep before you can return to your normal performance.

Lack of sleep has been associated with immune-system dysfunction, obesity, diabetes, and a variety of other illnesses. Impaired judgment and decreased alertness from lack of sleep can cause motor vehicle and work accidents, as well as diminished productivity. Getting less than 7-8 hours of sleep a night has even been found to shorten your life. Death from all causes is lowest among adults who get 7-8 hours of sleep, and significantly higher among people who sleep less than 7 or more than 9 hours.

What Causes Sleep Deprivation?

Sleep deprivation can be caused by:

Intentionally staying awake longer in order to do more

Use of stimulants, such as caffeine

Sleep disorders, such as sleep apnea

Anxiety or depression

Repeated awakenings from noise

Working at night

Jet lag and traveling across time zones

Medical illness causing pain or difficulty breathing

Sleep Apnea

Sleep apnea is a major cause of sleep deprivation. Obstructive sleep apnea, the most common form, is caused by obstruction of the nose and sometimes the throat as well, and results in lapses in breathing during sleep (the Greek word "apnea" literally means "without breath"). Sleep apnea has been linked to brain tissue damage and is a risk factor for hypertension, arrhythmias (abnormal heart rhythms), enlarged heart, heart attack, and stroke. Conversely, people with hypertension, atrial fibrillation (a type of arrhythmia), congestive heart failure, and coronary artery disease are more likely to have sleep apnea.

The material on this site is for informational purposes only and is not intended as medical advice. It should not be used to diagnose or treat any medical condition. Consult a licensed medical professional for the diagnosis and treatment of all medical conditions and before starting a new diet or exercise program. If you have a medical emergency, call 911 immediately.